ETH transferred given a transaction receipt

[frontier159]

When executing transactions that are expected to transfer ERC20 tokens, the pattern is to use parseEventLogs to summarise what tokens have actually transferred from/to the user (eg a DEX swap). The dapp can filter on the expected log addresses and also the to/from via the args.

However for native ETH its trickier.

• If the RPC supports tracing/debug then that could be used (albeit slow)
• A fallback could be to query the ETH balance change across blocks for that user. This isn't bulletproof though since there may be multiple value transfers in the same block (multiple txs in the block sending ETH to Alice) and also needs to take into account the transaction fee delta (if Alice submitted the tx)

I'm wondering what best practice is here using Viem and if it would make sense to have a builtin function to get the ETH value transfer which can do a fallback across methodologies.